As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
(CAN) ON CLIMB OUT THE CABIN RATE WAS CLIMBING HIGHER THAN NORMAL DUE TO SINGLE PACK. THE RATE STARTED TO DECREASE AND ACT NORMAL. RECEIVED A CABIN ALT CAUTION MESSAGE LEVELED OFF AND STARTED A DESCENT. THEN RECEIVED THE CABIN ALT WARNING MESSAGE. RAN THE QRC AND THE QRH AND COMPLETED THE MANUAL PRESSURIZATION PROCEDURE. CORRECTIVE ACTION: REMOVED AND REPLACED RT 10TH STAGE PRSOV. (TC# 20191004024)